<?php

    /**
     * PHPExcel_WorksheetIterator
     * Copyright (c) 2006 - 2015 PHPExcel
     * This library is free software; you can redistribute it and/or
     * modify it under the terms of the GNU Lesser General Public
     * License as published by the Free Software Foundation; either
     * version 2.1 of the License, or (at your option) any later version.
     * This library is distributed in the hope that it will be useful,
     * but WITHOUT ANY WARRANTY; without even the implied warranty of
     * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
     * Lesser General Public License for more details.
     * You should have received a copy of the GNU Lesser General Public
     * License along with this library; if not, write to the Free Software
     * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301  USA
     * @category   PHPExcel
     * @package    PHPExcel
     * @copyright  Copyright (c) 2006 - 2015 PHPExcel (http://www.codeplex.com/PHPExcel)
     * @license    http://www.gnu.org/licenses/old-licenses/lgpl-2.1.txt    LGPL
     * @version    ##VERSION##, ##DATE##
     */
    class PHPExcel_WorksheetIterator implements Iterator {
        /**
         * Spreadsheet to iterate
         * @var PHPExcel
         */
        private $subject;
        /**
         * Current iterator position
         * @var int
         */
        private $position = 0;

        /**
         * Create a new worksheet iterator
         * @param PHPExcel $subject
         */
        public function __construct(PHPExcel $subject = null) {
            // Set subject
            $this->subject = $subject;
        }

        /**
         * Destructor
         */
        public function __destruct() {
            unset($this->subject);
        }

        /**
         * Rewind iterator
         */
        public function rewind() {
            $this->position = 0;
        }

        /**
         * Current PHPExcel_Worksheet
         * @return PHPExcel_Worksheet
         */
        public function current() {
            return $this->subject->getSheet($this->position);
        }

        /**
         * Current key
         * @return int
         */
        public function key() {
            return $this->position;
        }

        /**
         * Next value
         */
        public function next() {
            ++$this->position;
        }

        /**
         * More PHPExcel_Worksheet instances available?
         * @return boolean
         */
        public function valid() {
            return $this->position < $this->subject->getSheetCount();
        }
    }
